Subjects will undergo characterization of biohumoral markers, a 75 g oral glucose tolerance test, imaging biomarkers (PET/CT, US, fMRI-MRS), genetic biomarkers (DNA and telomere damage) and inflammatory biomarkers (macrophage infiltration) before and after the 4-month lifestyle intervention period (physical exercise). By PET/CT it will be measured tissue-specific IR in skeletal muscle, adipose tissue, liver, myocardium and targeted brain regions. MRS will be used to measure organ steatosis in the skeletal muscle and liver, MRI will be used to measure fat masses in abdominal areas, and fMRI will be performed to assess activation in brain regions regulating cognition and appetite/energy control. US will be used to assess cardiovascular markers (IMT, strain and function).